Help me with a plan - Pic included!

[Acre4Me]

I'd put the coop inside...but what else does the barn do?
Chicken dust will get on everything.
Are vehicles parked in the barn? Exhaust can be bad for birds.
Pics of inside of barn would help, along with measurements of proposed area.

Outside dog pen (soon to be chicken run), will need a roof of at least mesh, solid would be better for winters. Might want to remove pavers.

Apron added to run to deter diggers.
Good examples of installation, tho I'd not recommend 1/2" HC...go with 14ga 1x2 or 1x1, will hold up much longer and is easier to lay flat.
http://www.backyardchickens.com/t/1110498/wire-around-coop#post_17093528
https://www.backyardchickens.com/threads/new-coop-project.1169916/page-2#post-18481208

There are 3 good reads linked in my signature, hope you can see them.

Thanks for the links - I'll look them over this weekend.

The barn may occasionally have a car in it, but generally not. I haven't measured the inside of the barn yet, but the car bays are potentially long enough for 2 cars each. The previous owner had a parade float type trailer parked in one bay, and 2 mower/tractor type items parked tandem in the other, and there are some fairly deep shelves along the wall in front of the car bays. There is also room to the side, with stairs to the loft area and then a workshop which appears to have been a mouse haven between the drawers and the insulation in the wall. There is definitely room for an interior coop (opened up to the exterior) in this barn. Currently, we are doing minor renovations and the garage areas are full of all that, plus all that the previous owner left behind (they downsized to a condo....). Good idea on removing pavers - Chickens like to scratch! With regards to a roof or shelter - yes, it should be easy to put mesh up to deter flying predators. I could also see building a low roof- like shelter that would peak above the coop opening (if we go with an interior building coop), otherwise, I would likely build the coop with space underneath. Will need to assess roof pitch and potential snow slide off the roof. We can get some pretty impressive snow events, but generally not like in the snow belt. Cleveland, OH gets lake effect snow, but we do not get that amount of snow.